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1大家好
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1🍏🍎🍏🍏🍏🍏🍏🍎🍏
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1没想到不等式成了万能公式
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1666
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1刚来
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2来看看
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45x²+1/x+1/4>lnx+4
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1来看看
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1来看看
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1来看看
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8
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1来看看
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1牛逼
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1来看看
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8对于正实数x、y、z,已知x+y+z=1 求证Σ(xy/(z+xy))^1/2 <=3/2 (我的做法:) Σ(xy/(z+xy))^1/2 <= 3Σ(xy/(z+xy)) = 9-3Σ(z/(1-x)(1-y)) = 9+3Σ(x^2-x)/(1-x)(1-y)(1-z) 然后做不下去哩…… 另法,设x<=y<=z(或柯西) Σ(xy/(z+xy))^1/2 <= Σ(x/(y+z)) 怀疑放过头了:-(